This invention concerns tubes made of thermoplastic material and provides an improved method and apparatus for forming such tubes into required shapes or configurations. As used herein, the term "tube" includes hoses, pipes and similar conduits, whether of single or multi-layer construction.
Tubes of plastics material are used in a wide number of applications and are commonly used in the automotive field as pipe connections for vapour, vent, hydraulic, fuel, coolant or oil lines. In such applications, the tube is often required to be of a specific shape or configuration.
Previously, such shapes have been obtained by special inserts positioned within the tube to conform the tube to the required shape followed by a heating or curing stage to set the required shape following which the insert is removed.
The use of such inserts has been considered essential to prevent the tube wall collapsing during shaping and this has restricted the shapes which can be produced. In particular, multiple bends cannot easily be obtained because of the complexity of the insert and the difficulty of removing the insert.
It is an object of the present invention to provide an improved method and apparatus for shaping thermoplastics tubes which overcomes the aforementioned disadvantages.